**Exhibit
21.1**
 
 
 **SUBSIDIARIES
      OF AMEREN CORPORATION**
      **AT
      DECEMBER 31, 2004**Name
    State
      or Jurisdiction
      of
      IncorporationAmeren
      Corporation
    MissouriAmeren
      Development Company
    MissouriAmeren
      Energy Communications, Inc.
    MissouriAmeren
      ERC, Inc.
    MissouriMissouri
      Central Railroad Company
    DelawareGateway
      Energy Systems, L.C.
    MissouriGateway
      Energy WGK Project, L.L.C.
    MissouriAmeren
      Energy, Inc.
    MissouriAmeren
      Energy Resources Company
    IllinoisAmeren
      Energy Development Company
    IllinoisAmeren
      Energy Generating Company
    IllinoisCoffeen
      and Western Railroad Company
    IllinoisAmeren
      Energy Fuels and Services Company
    IllinoisCowboy
      Railroad Development Co.
    ArkansasAFS
      Development Company, LLC
    IllinoisAmeren
      Energy Marketing Company
    IllinoisIllinois
      Materials Supply Co.
    IllinoisAmerenEnergy
      Medina Valley Cogen, (No. 4) L.L.C.
    IllinoisAmerenEnergy
      Medina Valley Operations, L.L.C.
    IllinoisAmerenEnergy
      Medina Valley Cogen (No. 2) L.L.C.
    IllinoisAmerenEnergy
      Medina Valley Cogen, L.L.C.
    IllinoisElectric
      Energy, Inc. (40% interest)
    IllinoisAmeren
      Services CompanyCentral
      Illinois Public Service Company
    IllinoisCIPS
      Energy Inc.
    IllinoisCIPSCO
      Investment Company
    IllinoisCIPSCO
      Securities Company
    IllinoisCIPSCO
      Leasing Company
    IllinoisCLC
      Aircraft Leasing Company
    IllinoisCLC
      Leasing Company A
    IllinoisCIPSCO
      Energy Company
    IllinoisCEC-ACLP
      Co.
    IllinoisCIPSCO
      Venture Company
    IllinoisUnion
      Electric Company
    MissouriUnion
      Electric Development Corporation
    MissouriElectric
      Energy, Inc. (40% interest)
    IllinoisCILCORP
      INC.Central
      Illinois Light Company
    IllinoisCILCO
      Exploration and Development Co.
    IllinoisAmerenEnergy
      Resources Generating Company
    IllinoisCILCO
      Energy Corporation
    IllinoisCILCORP
      Investment Management Inc.
    IllinoisCIM
      Air Leasing Inc.
    DelawareCIM
      Energy Investments Inc.
    IllinoisCIM
      Leasing Inc.
    DelawareCILCORP
      Lease Management Inc.
    DelawareCLM
      Inc., IV
    DelawareCLM
      Inc. - VII
    DelawareCLM
      Inc. - VIII
    DelawareCLM
      X, Inc.
    DelawareCLM
      Inc., VI
    DelawareCLM
      XI, Inc
    DelawareCLM
      XII, Inc.
    DelawareQST
      Enterprises Inc.
    IllinoisQST
      Energy Inc.
    IllinoisQST
      Energy Trading Inc.
    IllinoisCILCORP
      Infraservices Inc.
    IllinoisQST
      Inc.
    IllinoisESE
      Land Corporation
    IllinoisSavannah
      Resources Corp.
    CaliforniaESE
      Placentia Development Corporation
    IllinoisCalifornia/Nevada
      Development L.L.C.
    DelawareCILCORP
      Ventures Inc.
    IllinoisCILCORP
      Energy Services Inc.
    IllinoisAgricultural
      Research & Development Corp.
    IllinoisPeoria
      Medical Research Corp.
    IllinoisIllinois
      Power Company
    IllinoisIP
      Gas Supply Company
    IllinoisIllinois
      Power Transmission Company, LLC
    DelawareIllinois
      Power Securitization Limited Liability Company
    DelawareIllinois
      Power Special Purpose Trust
    DelawareIllinois
      Power Financing I
    DelawareIllinois
      Power Financing II
    Delaware